Tom,
Would you be able to smoke the butts prior to going over? They keep & reheat very well. Then, you could smoke 13 racks on the day of the event? The 2 and 3D should easily handle that many.
If I smoke butts for an event, I do everything as normal, but, instead of putting the wrapped butt in the cooler for a rest, I let it rest on the counter for an hour, and then seal the whole foil-wrapped butt in a FoodSaver bag. I then immerse in a sink full of ice water to rapidly cool it, then put in the fridge. To reheat, I place the foil-wrapped butt in a crock pot, and heat on low for 3-4 hours. Unwrap, and pull onsite. Works great, and tastes like the day you made it!
So, if you could smoke/save the butts to reheat there, and then smoke the ribs there, it might work out. At least, that's how I'd likely approach it.